Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash flows from operating activities
Net income	$ 43,626	$ 76,902
Adjustments to reconcile net income to net cash provided by operating activities:
Loss on extinguishment of debt	295	382
Change in fair value of derivative liability	(76)	(349)
Depreciation and amortization	6,462	1,728
Amortization of deferred financing costs and debt discount	50	226
Non-cash interest expense, net/ interest (income), net	(342)	286
Non-cash interest expense on non-recourse liability related to sale of future royalties	1,274	3,564
Non-cash royalty revenue	(3,708)	(3,464)
Share-based compensation expense	6,447	4,454
Deferred income tax provision	13,314	(42,377)
Changes in operating assets and liabilities:
Accounts receivable	(14,639)	(10,312)
Inventories	1,854	(4,866)
Prepaid expenses and other current assets	(2,712)	1,060
Accounts payable	(1,312)	(1,629)
Accrued sales deductions	17,829	12,900
Accrued expenses	2,769	2,503
Income taxes payable	6,482	811
Deferred licensing revenue	(202)	195
Other non-current liabilities	894	(140)
Net cash provided by operating activities	78,305	41,874
Cash flows from investing activities
Purchases of marketable securities	(78,938)	(31,194)
Sales and maturities of marketable securities	23,052	22,398
Purchases of property, plant and equipment	(1,273)	(1,302)
Deferred legal fees	(10,130)	(12,224)
Net cash used in investing activities	(67,289)	(22,322)
Cash flows from financing activities
Proceeds from issuance of common stock	4,510	1,255
Net cash provided by financing activities	4,510	1,255
Net increase in cash and cash equivalents	15,526	20,807
Cash and cash equivalents at beginning of period	66,398	33,498
Cash and cash equivalents at end of period	81,924	54,305
Supplemental cash flow information:
Cash paid for interest	134	247
Noncash financial activity:
Conversion of convertible notes and interest make-whole	4,546	2,138
Deferred legal fees included in accounts payable and accrued expenses	$ 1,337	$ 7,920